Hilton b



- M. B. REACH union 0! MANUFACTURING BASEBALL cam-Ens Oriiginal FiledSept. 5, 1924 Original No. 1,530,410,

vised,

m .sisted *Reissued Jan. 22, 1929.

UNITED ,VSTA

e rzoo res PATENT OFFICE. P

MILTON B. nnacrr, or onroornn, massacnnsn'rrs, AssIeNoa 1:0 as. BEACHdo, or PHILADELPHIA, PENNSYLVANIA, a CORPORATION or PENNSYLVANIA.

rtn'riron or MANurAcruaING BasnBArLL CENTERS.

I My present invention concerns an improved method of making theresilient centers used in manufacturing baseballs.

' The cork center baseball, as originally dehas been the "most popularplaying ball of its that manifests itselfin a certain percentage ofballs turned out, due to the established process of molding, whichoperation conof forming two half spheres of uncured stock in one ofwhich the cork center was deposited. The two halves were then fittedtogether and placed in a mold for molding. Under the heat and pressureof molding, the uncured stock flows, and it frequently hape pens thatthe cork center is distorted and displaced, with the result that thewound. baseball, in which this center is used, is made untrue. a

'The present invention aims to avoid this objection and provide a methodby which any and all. irregularities in the cork center will be avoidedand a uniform and perfect product be secured. v

To this end the invention comprises the novel method hereinafterdescribed and defined by the appended claims. In order that my inventionmaybe better understoodfl have appended hereto a drawing in which Thefigure shows enclosing shell, the different rubber portions which go tomake up the rubber shell being indicated by lines of division, althoughit 'will be understood that in the completed and vulcanized article nodivision lines would appear, as the various rubber parts are,-by theprocess of vulcanization, united into a omogeneous article, as will bewell understood by those skilled in the rubber art.

Referring by reference characters to this drawing, the cork center. isindicated by the numeral 1 and is of the character customarily used inthe manufacture of baseballs of the type referred to. Inmaking up myimproved enclosing shell, I first moldtwo half spheres of rubber whichare subjected in suitable molds having hemispherical cavities, tosufficient heat and pressure to .vulcanize the rub process beingpreferably discontinued just s ort of the complete curingstage, so thatthe sections, while not being completely cured, will yet have sufiicienther, the vulcamzin kind. A fault has existed, however,

1 they are the cork center with its dated March 17, 1925, Serial No.735,685, filed September 3, 1924. Application for reissuefiIed-November6, 1926. SerialNo. 146,833.

tenacity to cause them to retain their shape tion or displacement willbe avoided.' The hemispheres are indicated at 2 and 2 respectively,being duplicates of'each other, and. they are pieced together" to formthe complete sphere with the cork center 1 enclosed thereby, and a thinwasher of uncured gum placed between the abutting edges of thehemispheres, as indicated at 3. This washer is compounded of stock whichwill cure in a minimum amount of time, or specifically, of heat'required to complete the vulcanization of the hemispheres, which quicklycuring characteristics can be secured by any of the well known methodsfamiliar to. those in the'amount of time and degree I skilled in theart, as for example by the use i of the so-called accelerators. Afterthe hemispheres have been juxtaposed with the enclosed cork center andinterposed washer.

spheres of uncured rubber indicated at 4 and 4,having an interiordiameter corresponding to the exterior diameter of the hemispheres 2,and being made of a thickness not exceedin and preferably slightly less,than that of the washer, and being made of the same rubber compound asthe washer. The edges of the enclosing hemispheres 4 and 4 abut asshown. Thereafter the assembled parts are placed within a mold of. theusual type having a spherical mold cavity and submitted to the necessaryheat in the ordinary vulcanizing press, the result of which is that theuncured washer and enclosing shell are softened and caused to flow, asitis termed in therubber art, whereby the yet uncured washer andenclosing hemispheres are homogeneously united and cured and alsohomogeneousl united to the partially'cured inner hemispherical sections,while. at the same time, owingato the previous partial curing'of theinner cmisp'herical sections, flowing or distortion of these is vented.

I thus secure a cork center enclosed in a homogeneous outer shell withthe spherical contour of the cork center unchanged, and with the outersurface of the completed rubbersphere truly concentric to the surface ofreliably preset within or enclosed by two half shells used, the therubber of the shells to flow into the line 3 action, enclosing aspherical in the space between the edges of the hemiand thereafterhomogeneously joined to gether.

It is obvious in some cases the washer might be dispensed with and onlythe enclosing pressure of the mold causing of junction of thehemispheres and fulfil the function of the washer. In some cases alsothe washer alone might be used, and the shells omitted.

Having thus described my invention, what I claim is j ,1. Thehereindescribed method which consists in forming two hollow hemispheresof rubber compound, subjecting the same to vulcanization, enclosing aspherical co'rk center between said hemispheres, and securing themhomogeneously together by vulcanization, with theaid of aninterposedlayer of quick curing rubber compound.

2. The hereindescribed method which con; sists in forming two partiallycured hollovi hemispheres of rubber, bringing these hemispherestogether'to enclose a spherical cork center with an uncured layer ofrelatively quick curing compound interposed between the juxtaposed edgesof the hemispheres, and thereafter vulcanizing the article to cure theuncured layer and complete the cure of the hemispherical sections.

3. The hereindescribed method which consists in forming two partiallycured hollow hemispheres ofr'ubber, bringing these hemispheres togetherto' enclose a spherical cork center with an uncured Washer of relativelyquick curing compound interposed between the juxtaposed edges of thehemispheres, enclosing the said assembly inan outer envelope ofrelatively thin uncured rubber compounded to cure in the same time asthe aforesaid washer, and finally subjecting the whole to a vulcanizingaction to vulcanize the washer and envelope and complete thevulcanization of the hemispheres.

4. The hereindescribed method of making playing ball centers, whichconsists'in forming two .hollow hemispheres of rubber compound,subjecting the same to vulcanizing cork center between said hemispheres,and'homogeneously securing them together by causing a relatively quickcuring rubber compound-to flow spheres and be vulcanized thereto.

rubber washer interposed- 5. The hereindescribed method which consistsin forming two hemispheres of rubber compound, ;subjecting the same topartial vulcanization, enclosing a'spherical cork cen ter between saidhemispheres, andv securing them homogeneously together by vulcanization,with the'aid of a quick curing rubber compound.

6. A baseball center comprising a spherical core of cork, a shellcomprising two hemispheres of'rubber holdingsaid core and connected byvulcanization, and a rubber casing applied around the shell. L 7. Abaseball center'comprising a spherical core of cork,a shell comprisingtwo hemi-i sald core, and a spheres of; rubber holdin etween thejuxtaposed edges of said hemispheres and surrounding said core, Washerbeing connected by vulcanization.

- 8. The structure defined in claim 7 in further combination with arubbercasing applied around the shell and washer.

9. The herein described. methodof forming a homogeneous baseball centerconsisting in forming two hemispherical shells of a ru ber compoundvulcanized, to a state just short of a complete cure, bringing theshells together under pressure about a s herical core with a connectingcompound etween the edges of the shells, and then subjecting theassembly to a vulcanizing action sulficient to complete thevulcanization of, the shells.

10. The hereindescribed method of forming a homogeneous baseball centerconsisting in providing two hemispherical shells of a rubber compoundvulcanized to a state just short'of a'complete cure, bringing the shellstogether under pressure about a spherical core and with a quick curingrubber comsaid hemispheres and pound interposed between the juxtaposededges of'the shells, and then subjecting the assembly to a vulcanizingaction sufficient to complete the'vulcanization of the shells andefi'ect vulcanization of the interposed COIIipound.

11. The herein described method of forming a baseball center consistingin providing two hemispherical shells of a rubber compound vulcanized toa state just short of a complete cure, bringing the shells togetherabout a spherical cork center with apquick' .curing rubber. compoundinterposed between 12 A baseball centera ssemblycomprising a sphericalcore, two hemispherical shells of rubber enclosing the same, and twohemispherical shells of rubber enclosing the aforesaid assembly andconnected by vulcanizetion at their juxtaposed edges.

13', A baseball center comprising a spherical cork center, twohemispherical shells of rubber enclosing the same and connected byvulcanization at their juxtaposed edges through an interposed compounddifferent in.

character from thatcmplo ed in the shells,

and two hemispherical she 1s of rubber enclosing the aforesaid assemblyand connected by vulcanization at the juxtaposed edges and interiorly tothe periphery of the first named shells.

In testimony whereof I ufiix In signature.

MILTON B. EACH.

